java - JTree representing a graph -

i using jtree swing utility represent tree have loops. have single node called root, of children point other parts of tree, not making true tree, rather graph.

my java application keeps locking up, (no exceptions being thrown, no stack overflow... etc) when try use little gray arrows expand , contract parts of graph.

my question is, jtree require none of defaulmutabletreenodes not contain loop?

if so, how represent using jtree utility. example, when debugging application in eclipse, , can infinitely use variable tree in debug mode keep on looking through looped object. behavior looking for.

any suggestions?

i don't think it's problem nodes in jtree loop on themselves. apparently have problem "expand all" button, makes sense because expand method go recursively through nodes until have no sons.

jtree not have expand button default, i'm guessing yours customized...? suggestion either remove button, or customize code stop expansion if findind node expanded higher in hierarchy.